The Thai Forest Tradition started around 1900 with Ajahn Mun Bhuridatto, who wanted to practice Buddhist monasticism, and its meditative practices, according to the standards of pre-sectarian Buddhism. After studying with Ajahn Sao Kantasīlo, and wandering through the north-east of Thailand, Ajahn Mun started to teach in North-East Thailand. He strived for a revival of the oldest Buddhism, insisting on a strict observance of the Buddhist monastic code, known as the Vinaya, and teaching the actual practice of jhana and the realisation of nibbana.

Initially Ajaan Mun's teachings were met with opposition, but in the 1930s his group was acknowledged as a formal faction of Thai Buddhism, and in the 1950s the relationship with the royal and religious establishment improved. In the 1960s western students started to be attracted, and in the 1970s Thai-oriented meditation groups spread in the west.